Jim was a good friend of mine; he was quite an unusual looking lad. I knew that he always wanted to settle down with a girl, but he wasn't a good conversationalist, and that compounded the problem he had with his looks. It just never happened for him. He died of a drink-related illness in his late thirties. Patrick was good looking, friendly but always intensely shy. He was dominated by his parents and found it hard to cope. He ended up with mental problems and he was finally found floating in a local dock. He never married or had children. A girl in my class died as a result of anaphylactic shock after being stung by a bee. Ron was in my class too. He died at twelve, with his sister, in a fire. (All names changed.)Ok! Ok! I do have some friends left.

My point is that all of the above people failed to pass on their genes. With a different roll of the genetic dice each of them, with the exception of Ron, would probably have families today. (The fire that killed Ron was a pure accident and therefore a random event outside of genetic influence.) When tragedies like this happen we don't think of them as being examples of natural (or sexual) selection, but that is, almost certainly, exactly what they are. I would be prepared to bet that each of you would be able to think of examples, like this, from within your own experience.

Much of the earlier part of "The Red Queen", reinforces this point; the book shows just how potent, powerful and all-pervasive natural selection is. It is a highly dynamic system; selective pressure is everywhere. It is remorseless, indefatigable and ubiquitous. Even if one accepts that the Red Queen hypothesis does demonstrate that this does not mean that adaptive change is happening all the time. Natural selection must always be active.

It should be obvious that given the awesome complexity of the "gene wars" that Ridley eloquently illuminates in the book, we humans could not possibly have escaped this all-pervasive pressure, because we too are part of nature.

Why, then, does the implicit assumption that evolution is not happening in modern populations seem to prevail? Ok Ridley is not the chief proponent of this view, Steven Rose and Steve Jones would be better targets for my attack; but here goes:

Down to specifics. One reason that the "Fully-Evolved-Human" fallacy has arisen is that it is clear that much natural selection in humans is genuinely not active. Lets ignore sexual selection, for the moment for the sake of simplicity. We can see that it is obvious that it simply doesn't matter whether we are big or small, fat or thin, whether we can run fast, whether we are clever enough to outwit predators, whether we are good leaders. Even if we are severely disabled and unable to contribute anything to society we might still survive long enough to reach breeding age. All this is unarguable and I don't (argue). There is probably also no argument that natural selection is not active in the role of disease resistance. The running battle against pathogens is probably continuing at the about the same rate as it always was, subject to the obvious consideration that we (at least in the West) are probably better nourished, and better able to fight disease than we might have been in our ancestral past. But this effect won't be regarded as sexy by most people - because due to the Red Queen effect it won't mean that humans are changing in any way we would generally think interesting.

But are other forms of natural selection active in modern human populations, acting, perhaps, on their BEHAVIOUR as opposed to their morphology? And - this is the BIG one - could there be adaptive evolution going on now?

Can it be that Ridley, Pinker and some (and maybe all) of the other modern science writers have been subsumed into a cultural milieu, where really important issues like this are ignored, or dodged.

When I asked Steven Pinker, in the web chat, about whether he thought that natural selection against what I call the "Need for Speed Effect" was happening in modern Western populations his answer was interesting, but perhaps not in the way he might have expected. He said:

Quote:Selection against speed -- once again, the key quesiton is how widespread and for how long that selection pressure lasts. A phenomenon of the last 50 years in a few industiralized countries will not affect the species, especially if the total number killed is relatively small -- e.g., 40,000 deaths a year in the US, which has something like 300 million people.

Why did Steve Pinker think that I was asking about the changes we might experience within our own lifetime? Shifts in gene frequency as a result of natural selection will surely be measured over genealogical time, and as a proportion of live births. The correct average percentage change would be: that subset of the number killed in car accidents who died because of their own predisposition for the enjoyment of speed, over a period of time, against the number born in that same time period. i.e. the number killed in an average year against the total number born in an average year. I don't believe that Steve Pinker would not have understood the distinction. He thought I was asking a different question. He seemed to think that I wanted to know what effect it would have on a population in real time. Maybe he would have thought it odd that I would ask about gene frequency changes over genealogical time. Gene frequency changes could never affect us on a day-to-day basis, and - as he pointed out - it would be impossible to predict how evolutionary change might affect us in the future. Both these points, incidentally, I entirely accept

I suspect that Steven Pinker's philosophical project is to improve and refine the social sciences in light of evolutionary psychology (or perhaps more accurately to dissolve the social sciences into evolutionary psychology as he thinks - probably rightly - that it has better scientific credentials). His aim being that social science might be more effective at dealing with human problems. I admire what he is trying to do; I think that his project is laudable and important, but the changes, he is interested in, happen in real time. So perhaps he can be forgiven for misunderstanding, or maybe it was my fault for not framing my question properly.

My philosophical project is quite different. I want human beings to understand their true place in nature. Why do I bother concern myself with evolutionary change if it cannot possibly have any significant effect on our day-to-day lives, and if it is not possible to predict trends or read the future?

Our view of what it means to be human is important. If we could be evolving, as I suggest we might be, in whatever direction, it means that we are not well adapted to the world we are living in, and this could profoundly change the way we see ourselves. If adaptive change is happening, it underlines the point that passively accepting innate behaviour - which might be inappropriate in our modern world - and just doing what our innate behaviour tells us to do, because it feels right, could be an appalling and dangerous mistake.

So in what way is the cultural milieu affecting their judgement? Where have they gone wrong?

They are wrong because although we may not be able to predict how change might happen in the future, and it might be - because of the "wilderness of mirrors" problem I identified in my earlier posts - difficult to say how it is currently progressing. It is emphatically not true to imply that selection is not happening. Nor, even, is it safe to say that it is not happening in a co-ordinated and steady direction.

Now to the really interesting part: The point they have lost in the cultural milieu is this: We did not evolve to fit the world in which we live now; each of us evolved the appropriate behaviour for a member of some ancient tribe on the Pleistocene savannah. Now because we no longer live in that environment it is not likely that any active selective process will be maintaining our behaviour in any way that would have been appropriate in the Pleistocene. To put it another way, any selective effects in modern populations are likely to be leading to ADAPTIVE CHANGE rather than maintaining stasis.

You may have noticed that nothing I have said rules out the possibility of hypothesising about changes that might have been effected during historical time. I won't go into more detail about this - this post is getting long enough. But we are not the supreme, super-intelligent species we seem to think we are. We almost certainly have behavioural attributes that are inappropriate to us in the modern world, and we should not think that evolution will not be adjusting gene frequencies in a consistent direction if any of the inappropriate behaviours are leading any of us to fail to pass on our genes. It should not be too difficult to work out what the inappropriate behaviours are, nor should it be impossible to identify possible trends in the historical record.

Are there good reasons why neither Ridley nor Pinker nor the others want to address these questions? There could be! They might well have thought this through and decided to leave it alone. It may not be cultural influence that is influencing their decision. After all much of this calls for subjective judgement because we don't yet know which genes are implicated in which particular behavioural attribute so we have no quantifiable data about how gene frequencies may vary from population to population due to selective effects during historical or pre-historical time. Then there is the problem that if we start arguing that the behaviour of different population groups might differ, it could be construed as providing ammunition for racist or extreme nationalist views. (This is an extremely good point, but it can be completely undermined if there is a case for putting tribalism on our list of proscribed archaic behaviour.) Or perhaps they think that at this stage all we can do is hypothesise and this might be outside of the remit of good scientists.

I agree with pretty much everything you say, except your implication that Ridley would disagree. I just finished reading

Quote:. . .for more than a million years people lived in a way that couldn't have changed much. They inhabited grasslands and woodland savannas, first in Africa, later in Eurasia, and eventually in Australasia and the Americas. They hunted animals for food, gathered fruits and seeds, and were highly social within each tribe but hostile toward members of other tribes. Don Symons refers to this combination of time and place as the "environment of evolutionary adaptedness," or EEA, and he believes it is central to human psychology. People cannot be adapted to the present or the future; they can only be adapted to the past.

BUT on the next page:

Quote:Another group of biologists at Michigan rejects these EEA arguments altogether with two arguments. First, the most critical feature of the EEA is still with us. It is other people. Our brains grew so big not to make tools but to psychologize one another. The lesson of socioecology is that our mating system is determined not by ecology but by other people

Ridley might not disagree - it is just that I think that these points are not pressed home to the general public hard enough.

I bought "The Runaway Brain" at your suggestion. I am still wading through Russel's "History of Western Philosophy", which is a bit of a doorstopper but "Runaway" is next on my list.

The kind of book I had in mind wouldn't be popular science. I think my my book which is a hybrid between pop science and a novel might have a much broader appeal. I think the two aspects of the book will feed each other and lead to a massively powerful effect.

I too believe adaptive evolution is active, but is taking somewhat of a back seat presently. The best example is the human population explosion despite birth control. Yes, I do agree that modern selective pressure is changing the gene mix, but in order for it to have a profound noticeable effect, it must either continue over significant time or be severely selective. Example: elephants with tusks have only 25% chance of having offspring due to ivory trade. Result? A huge expanse of gene mix that create, what was once rare, tuskless elephants in less than 50 years.

Yes, behavior that loves speed and gets killed by it does reduce the expression in that gene pool of speed. On the other hand if such reckless behavior is also tied to wild and unprotected sex, then that geneplex is secure and may actually increase its mix due to shorter generations (between birth and birth) and those that survive speed may also have larger families. Another irresponsible trait is drug use. Yes, this kills many parents or would be parents, yet on the other hand, this same group has a much higher and earlier teen pregnancy problem. In the old world, these children would have a much lower survival rate, but in the modern world, apparently all children survive. So once again, the opposite will occur in the modern world. The gene expressing vulnerability to drugs will increase in the modern world of contraceptives. This paragraph expresses the "wilderness of mirrors."

To me, the only strong selective pressure that presently exists in the modern world is the use of contraceptives. Like elephant tusks, it is absolute and highly selective. It is less vulnerable to the complexity of "wilderness of mirrors." It does not matter whether the cause of use of contraceptives is cultural (memes) or genetic (genes) or a combination of both. Voluntary contraceptives is the executioner of any trait of genes or cultural memes that practice it. It will rapidly be displaced by behavior that is resistant to it, whether expressed culturally or genetically. It is absolute and it is swift. But perhaps this point is irrelevant. We have a race against time as humanity enters the environmental "bottleneck" of this century due to overpopulation and excessive resource consumption. It is in this century that the old horses of famine, drought, disease, and the breakdown of social institutions appear and began to decimate our numbers. And, no, this is not considered selective pressure on humanity as all genes and cultures will be dramatically affected. The small gene pool that will be left will be an accidental throw of the dice, as what happened to humanity some 75 to 100 thousand years ago, our last great bottleneck that humanity passed through.

It is time that the best of culture and genes be pooled in private protected areas awaiting the crisis, and when over, re-seed the world with the lesson of the past remembered. Think of it as a dry Noah's Ark.

Quote:Yes, behavior that loves speed and gets killed by it does reduce the expression in that gene pool of speed. On the other hand if such reckless behavior is also tied to wild and unprotected sex

I agree that if reckless behaviour is included in the claim it would very much place it in the "wilderness of mirrors". That is why I was specific about the pleasurable response to speed as being the sole behavioural attribute I was interested in, but you have a point that recklessness might have to be involved. It is a complicated business this.

You might have a point about contraception if you include genetic and memetic influences, - selection can weed out memes as well as genes of course - but I am not clear quite how this might work.

I'm not sure about your idea that food will run out during this century though, technology has kept ahead of it until now and it might well stay ahead. If things got that bad it could happen that the "China" model of limiting the number of offspring might become prevalent, even in the West. So there would be something we could do.

I think that there is a bigger danger from global warming. The carbon levels have taken many many decades to get this bad. (New research suggests that the oceans are now more acid than they have ever known to have been, due to the co2 absorption.) If a watershed is reached where the Amazon rainforest starts to dry out and return the carbon, from its vast carbon sink, to the atmosphere,there will not be a blind thing we could do about it; technology couldn't help us.

The other great danger is nuclear war. Jared Diamond put it well in his book - I think it was "The Third Chimpanzee" - he said (something like) we might either die in a slow cooker, or in a bright flash of flame.

Quote:Why did Steve Pinker think that I was asking about the changes we might experience within our own lifetime? Shifts in gene frequency as a result of natural selection will surely be measured over genealogical time, and as a proportion of live births.

My guess would be that Pinker limited the time scale of natural selection in this case because the danger of speed-induced death (i.e. automobile or motorcycle accidents) has only been around for at most 60 or 70 years (I know it's technically possible to die in a Ford Model T crash, just somewhat less likely.) If this trend persists, or even becomes more significant in the years to come, we might indeed see selection for cautiousness, though as it has been pointed out, we have to consider all aspects of such behavioural patterns, since it is often very difficult for evolution to single out a particular part of a threat to avoid (e.g. humans are afraid of all spiders, not just venomous spiders.)

Quote:it is often very difficult for evolution to single out a particular part of a threat to avoid

This is all a very complex area. But that doesn't mean that evolutionary change is not happening - just that it is hard to quantify.

I chose "need for speed" as it seems to me to be the most salient effect. It might seem an unimportant observation given that it is - as you said - a recent phenomenon and it is likely that future technological change might cancel or reverse the effect. However the point is that in the West, in this historical period, human beings are evolving. That is the point and I think a pretty important one, in that it changes the way we might think of ourselves.

Recklessness is a different trait and this is subject to the plausible counter effect that men who are more reckless might be more inclined to take less care with contraception and therefore the selective effect might be compromised, so I think of the recklessness trait being firmly in the "wilderness of mirrors" category. But just because a trait can be considered as being in the "wilderness of mirrors" it does not necessarily mean that it is not a real and persistent selective effect or that it is not leading to a consistent change in gene frequency it may just be that any possible change is difficult, or impossible, to quantify.

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